NO
(ignored inputs)COMMENT submitted by: Akihisa Yamada used by COPS #1277
Rewrite Rules:
   [ f(f(?x)) -> f(g(f(?x))),
     f(?x) -> ?x ]
Apply Direct Methods...
Inner CPs:
   [ f(?x_1) = f(g(f(?x_1))),
     f(f(g(f(?x)))) = f(g(f(f(?x)))) ]
Outer CPs:
   [ f(g(f(?x))) = f(?x) ]
not Overlay, check Termination...
Terminating, not WCR
Knuth & Bendix
Direct Methods: not CR

Combined result: not CR
1650.trs: Success(not CR)
(0 msec.)